Judge Henry Hudson's opinion declaring the individual mandate unconstitutional is a curious thing. The federal government basically argued that (a) PPACA regulates the healthcare market and (b) the healthcare market is plainly an instance of interstate commerce. So broad regulation of the healthcare market is well within the purview of the Commerce Clause of the constitution. Furthermore, since individuals get sick and receive medical care whether or not they have healthcare coverage (and whether or not they can pay for it), a decision not to buy health insurance has a significant effect on the healthcare market. Therefore, forcing people to buy healthcare coverage is a reasonable provision in a bill meant to regulate the healthcare market.
But here's what Hudson has to say about that:
If a person’s decision not to purchase health insurance at a particular point in time does not constitute the type of economic activity subject to regulation under the Commerce Clause, then logically an attempt to enforce such provision under the Necessary and Proper Clause is equally offensive to the Constitution.
I'm no lawyer, but that's just not right. As defined by Hudson, the Necessary and Proper Clause serves no purpose at all, because anything that isn't specifically authorized elsewhere in the constitution logically can't be authorized by the Necessary and Proper Clause either. But the Necessary and Proper Clause isn't meant to merely add an exclamation point to other provisions of the constitution. Rather, it says that rationally related subsidiary means are constitutional as long as the overall ends are constitutional. To make Hudson's paragraph meaningful and non-tautological, it would have to read like this:
If regulation of the healthcare market does not constitute the type of economic activity subject to regulation under the Commerce Clause, then logically an attempt to enforce an individual mandate under the Necessary and Proper Clause is equally offensive to the Constitution.
This would be true. But no one is arguing that Congress can't regulate the healthcare market, so it also doesn't matter. The entire issue at stake here is whether the individual mandate is a reasonable means to implement a piece of regulation that, broadly speaking, is clearly within Congress's purview. But because Hudson peremptorily sweeps this away with his odd tautology, he never really engages with the key question in the entire case.
For reasons that Jack Balkin summarizes well here, I think the Supreme Court will end up agreeing that the individual mandate is well within the range of means that Congress can choose from in order to regulate a large and important sector of interstate commerce. But whether they do or not, it's hard to believe that they or any other court will take Hudson's facially preposterous reading of the Necessary and Proper Clause seriously.